//! Module with the definition of the WopbsKey (WithOut padding PBS Key).
//!
//! This module implements the generation of another server public key, which allows to compute
//! an alternative version of the programmable bootstrapping. This does not require the use of a
//! bit of padding.
#[cfg(all(test, feature = "experimental"))]
mod test;

use serde::{Deserialize, Serialize};

#[derive(Clone, Serialize, Deserialize)]
pub struct WopbsKey {
    wopbs_key: crate::shortint::wopbs::WopbsKey,
}

#[cfg(feature = "experimental")]
pub use experimental::*;

#[cfg(feature = "experimental")]
mod experimental {
    pub use crate::core_crypto::commons::parameters::{CiphertextCount, PlaintextCount};
    use crate::core_crypto::prelude::*;
    use crate::integer::client_key::utils::i_crt;
    use crate::integer::{ClientKey, CrtCiphertext, IntegerCiphertext, RadixCiphertext, ServerKey};
    use crate::shortint::ciphertext::{Degree, NoiseLevel};
    use crate::shortint::WopbsParameters;

    use crate::shortint::wopbs::WopbsLUTBase;

    use super::WopbsKey;

    use rayon::prelude::*;

    #[must_use]
    pub struct IntegerWopbsLUT {
        inner: WopbsLUTBase,
    }

    impl IntegerWopbsLUT {
        pub fn new(
            small_lut_size: PlaintextCount,
            output_ciphertext_count: CiphertextCount,
        ) -> Self {
            Self {
                inner: WopbsLUTBase::new(small_lut_size, output_ciphertext_count),
            }
        }
    }

    impl TryFrom<Vec<Vec<u64>>> for IntegerWopbsLUT {
        type Error = &'static str;

        fn try_from(value: Vec<Vec<u64>>) -> Result<Self, Self::Error> {
            let small_lut_size = value[0].len();
            if !value.iter().all(|x| x.len() == small_lut_size) {
                return Err("All small luts must have the same size");
            }

            let small_lut_count = value.len();

            Ok(Self {
                inner: WopbsLUTBase::from_vec(
                    value.into_iter().flatten().collect(),
                    CiphertextCount(small_lut_count),
                ),
            })
        }
    }

    impl AsRef<WopbsLUTBase> for IntegerWopbsLUT {
        fn as_ref(&self) -> &WopbsLUTBase {
            &self.inner
        }
    }

    impl AsMut<WopbsLUTBase> for IntegerWopbsLUT {
        fn as_mut(&mut self) -> &mut WopbsLUTBase {
            &mut self.inner
        }
    }

    impl std::ops::Index<usize> for IntegerWopbsLUT {
        type Output = [u64];

        fn index(&self, index: usize) -> &Self::Output {
            self.as_ref().get_small_lut(index)
        }
    }

    impl std::ops::IndexMut<usize> for IntegerWopbsLUT {
        fn index_mut(&mut self, index: usize) -> &mut Self::Output {
            self.as_mut().get_small_lut_mut(index)
        }
    }

    /// ```rust
    /// use tfhe::integer::wopbs::{decode_radix, encode_radix};
    ///
    /// let val = 11;
    /// let basis = 2;
    /// let nb_block = 5;
    /// let radix = encode_radix(val, basis, nb_block);
    ///
    /// assert_eq!(val, decode_radix(&radix, basis));
    /// ```
    pub fn encode_radix(val: u64, basis: u64, nb_block: u64) -> Vec<u64> {
        let mut output = vec![];
        //Bits of message put to 1éfé
        let mask = basis - 1;

        let mut power = 1_u64;
        //Put each decomposition into a new ciphertext
        for _ in 0..nb_block {
            let mut decomp = val & (mask * power);
            decomp /= power;

            // fill the vector with the message moduli
            output.push(decomp);

            //modulus to the power i
            power *= basis;
        }
        output
    }

    pub fn encode_crt(val: u64, basis: &[u64]) -> Vec<u64> {
        let mut output = vec![];
        //Put each decomposition into a new ciphertext
        for i in basis {
            output.push(val % i);
        }
        output
    }

    //Concatenate two ciphertexts in one
    //Used to compute bivariate wopbs
    fn ciphertext_concatenation<T>(ct1: &T, ct2: &T) -> T
    where
        T: IntegerCiphertext,
    {
        let mut new_blocks = ct1.blocks().to_vec();
        new_blocks.extend_from_slice(ct2.blocks());
        T::from_blocks(new_blocks)
    }

    pub fn encode_mix_radix(mut val: u64, basis: &[u64], modulus: u64) -> Vec<u64> {
        let mut output = vec![];
        for basis in basis.iter() {
            output.push(val % modulus);
            val -= val % modulus;
            let tmp = (val % (1 << basis)) >> (f64::log2(modulus as f64) as u64);
            val >>= basis;
            val += tmp;
        }
        output
    }

    // Example: val = 5 = 0b101 , basis = [1,2] -> output = [1, 1]
    /// ```rust
    /// use tfhe::integer::wopbs::split_value_according_to_bit_basis;
    /// // Generate the client key and the server key:
    /// let val = 5;
    /// let basis = vec![1, 2];
    /// assert_eq!(vec![1, 2], split_value_according_to_bit_basis(val, &basis));
    /// ```
    pub fn split_value_according_to_bit_basis(value: u64, basis: &[u64]) -> Vec<u64> {
        let mut output = vec![];
        let mut tmp = value;
        let mask = 1;

        for i in basis {
            let mut tmp_output = 0;
            for j in 0..*i {
                let val = tmp & mask;
                tmp_output += val << j;
                tmp >>= 1;
            }
            output.push(tmp_output);
        }
        output
    }

    /// ```rust
    /// use tfhe::integer::wopbs::{decode_radix, encode_radix};
    ///
    /// let val = 11;
    /// let basis = 2;
    /// let nb_block = 5;
    /// let radix = encode_radix(val, basis, nb_block);
    ///
    /// assert_eq!(val, decode_radix(&radix, basis));
    /// ```
    pub fn decode_radix(val: &[u64], basis: u64) -> u64 {
        let mut result = 0_u64;
        let mut shift = 1_u64;
        for v_i in val.iter() {
            //decrypt the component i of the integer and multiply it by the radix product
            let tmp = v_i.wrapping_mul(shift);

            // update the result
            result = result.wrapping_add(tmp);

            // update the shift for the next iteration
            shift = shift.wrapping_mul(basis);
        }
        result
    }

    impl From<crate::shortint::wopbs::WopbsKey> for WopbsKey {
        fn from(wopbs_key: crate::shortint::wopbs::WopbsKey) -> Self {
            Self { wopbs_key }
        }
    }

    impl WopbsKey {
        /// Generates the server key required to compute a WoPBS from the client and the server
        /// keys. # Example
        /// ```rust
        /// use tfhe::integer::gen_keys_radix;
        /// use tfhe::integer::wopbs::*;
        /// use tfhe::shortint::parameters::parameters_wopbs_message_carry::WOPBS_PARAM_MESSAGE_1_CARRY_1_KS_PBS;
        /// use tfhe::shortint::parameters::PARAM_MESSAGE_1_CARRY_1_KS_PBS_GAUSSIAN_2M64;
        ///
        /// // Generate the client key and the server key:
        /// let (cks, sks) = gen_keys_radix(PARAM_MESSAGE_1_CARRY_1_KS_PBS_GAUSSIAN_2M64, 1);
        /// let wopbs_key = WopbsKey::new_wopbs_key(&cks, &sks, &WOPBS_PARAM_MESSAGE_1_CARRY_1_KS_PBS);
        /// ```
        pub fn new_wopbs_key<IntegerClientKey: AsRef<ClientKey>>(
            cks: &IntegerClientKey,
            sks: &ServerKey,
            parameters: &WopbsParameters,
        ) -> Self {
            Self {
                wopbs_key: crate::shortint::wopbs::WopbsKey::new_wopbs_key(
                    &cks.as_ref().key,
                    &sks.key,
                    parameters,
                ),
            }
        }

        /// Deconstruct a [`WopbsKey`] into its constituents.
        pub fn into_raw_parts(self) -> crate::shortint::wopbs::WopbsKey {
            self.wopbs_key
        }

        /// Construct a [`WopbsKey`] from its constituents.
        pub fn from_raw_parts(wopbs_key: crate::shortint::wopbs::WopbsKey) -> Self {
            Self { wopbs_key }
        }

        pub fn new_wopbs_key_only_for_wopbs<IntegerClientKey: AsRef<ClientKey>>(
            cks: &IntegerClientKey,
            sks: &ServerKey,
        ) -> Self {
            Self {
                wopbs_key: crate::shortint::wopbs::WopbsKey::new_wopbs_key_only_for_wopbs(
                    &cks.as_ref().key,
                    &sks.key,
                ),
            }
        }

        /// Computes the WoP-PBS given the luts.
        ///
        /// This works for both RadixCiphertext and CrtCiphertext.
        ///
        /// # Example
        ///
        /// ```rust
        /// use tfhe::integer::gen_keys_radix;
        /// use tfhe::integer::wopbs::*;
        /// use tfhe::shortint::parameters::parameters_wopbs_message_carry::WOPBS_PARAM_MESSAGE_2_CARRY_2_KS_PBS;
        /// use tfhe::shortint::parameters::PARAM_MESSAGE_2_CARRY_2_KS_PBS_GAUSSIAN_2M64;
        ///
        /// let nb_block = 3;
        /// //Generate the client key and the server key:
        /// let (cks, sks) = gen_keys_radix(PARAM_MESSAGE_2_CARRY_2_KS_PBS_GAUSSIAN_2M64, nb_block);
        /// let wopbs_key = WopbsKey::new_wopbs_key(&cks, &sks, &WOPBS_PARAM_MESSAGE_2_CARRY_2_KS_PBS);
        /// let mut moduli = 1_u64;
        /// for _ in 0..nb_block {
        ///     moduli *= cks.parameters().message_modulus().0;
        /// }
        /// let clear = 42 % moduli;
        /// let ct = cks.encrypt(clear);
        /// let ct = wopbs_key.keyswitch_to_wopbs_params(&sks, &ct);
        /// let lut = wopbs_key.generate_lut_radix(&ct, |x| x);
        /// let ct_res = wopbs_key.wopbs(&ct, &lut);
        /// let ct_res = wopbs_key.keyswitch_to_pbs_params(&ct_res);
        /// let res: u64 = cks.decrypt(&ct_res);
        ///
        /// assert_eq!(res, clear);
        /// ```
        pub fn wopbs<T>(&self, ct_in: &T, lut: &IntegerWopbsLUT) -> T
        where
            T: IntegerCiphertext,
        {
            let total_bits_extracted = ct_in.blocks().iter().fold(0usize, |acc, block| {
                acc + f64::log2((block.degree.get() + 1) as f64).ceil() as usize
            });

            let extract_bits_output_lwe_size = self
                .wopbs_key
                .wopbs_server_key
                .key_switching_key
                .output_key_lwe_dimension()
                .to_lwe_size();

            let mut extracted_bits_blocks = LweCiphertextList::new(
                0u64,
                extract_bits_output_lwe_size,
                LweCiphertextCount(total_bits_extracted),
                self.wopbs_key.param.ciphertext_modulus,
            );

            let mut bits_extracted_so_far = 0;

            // Extraction of each bit for each block
            for block in ct_in.blocks().iter().rev() {
                let message_modulus = self.wopbs_key.param.message_modulus.0;
                let carry_modulus = self.wopbs_key.param.carry_modulus.0;
                let delta = (1u64 << 63) / (carry_modulus * message_modulus);
                // casting to usize is fine, ilog2 of u64 is guaranteed to be < 64
                let delta_log = DeltaLog(delta.ilog2() as usize);
                let nb_bit_to_extract = f64::log2((block.degree.get() + 1) as f64).ceil() as usize;

                let extract_from_bit = bits_extracted_so_far;
                let extract_to_bit = extract_from_bit + nb_bit_to_extract;
                bits_extracted_so_far += nb_bit_to_extract;

                let mut lwe_sub_list =
                    extracted_bits_blocks.get_sub_mut(extract_from_bit..extract_to_bit);

                self.wopbs_key.extract_bits_assign(
                    delta_log,
                    block,
                    ExtractedBitsCount(nb_bit_to_extract),
                    &mut lwe_sub_list,
                );
            }

            let vec_ct_out = self
                .wopbs_key
                .circuit_bootstrapping_vertical_packing(lut.as_ref(), &extracted_bits_blocks);

            let mut ct_vec_out = vec![];
            for (block, block_out) in ct_in.blocks().iter().zip(vec_ct_out) {
                ct_vec_out.push(crate::shortint::Ciphertext::new(
                    block_out,
                    Degree::new(block.message_modulus.0 - 1),
                    NoiseLevel::NOMINAL,
                    block.message_modulus,
                    block.carry_modulus,
                    block.pbs_order,
                ));
            }
            T::from_blocks(ct_vec_out)
        }

        /// # Example
        /// ```rust
        /// use tfhe::integer::gen_keys_radix;
        /// use tfhe::integer::wopbs::WopbsKey;
        /// use tfhe::shortint::parameters::parameters_wopbs_only::WOPBS_ONLY_4_BLOCKS_PARAM_MESSAGE_2_CARRY_2_KS_PBS;
        ///
        /// let nb_block = 3;
        /// //Generate the client key and the server key:
        /// let (cks, sks) = gen_keys_radix(WOPBS_ONLY_4_BLOCKS_PARAM_MESSAGE_2_CARRY_2_KS_PBS, nb_block);
        /// let wopbs_key = WopbsKey::new_wopbs_key_only_for_wopbs(&cks, &sks);
        /// let mut moduli = 1_u64;
        /// for _ in 0..nb_block {
        ///     moduli *= cks.parameters().message_modulus().0;
        /// }
        /// let clear = 15 % moduli;
        /// let ct = cks.encrypt_without_padding(clear);
        /// let lut = wopbs_key.generate_lut_radix_without_padding(&ct, |x| 2 * x);
        /// let ct_res = wopbs_key.wopbs_without_padding(&ct, &lut);
        /// let res: u64 = cks.decrypt_without_padding(&ct_res);
        ///
        /// assert_eq!(res, (clear * 2) % moduli)
        /// ```
        pub fn wopbs_without_padding<T>(&self, ct_in: &T, lut: &IntegerWopbsLUT) -> T
        where
            T: IntegerCiphertext,
        {
            let total_bits_extracted = ct_in.blocks().iter().fold(0usize, |acc, block| {
                acc + f64::log2((block.message_modulus.0 * block.carry_modulus.0) as f64) as usize
            });

            let extract_bits_output_lwe_size = self
                .wopbs_key
                .wopbs_server_key
                .key_switching_key
                .output_key_lwe_dimension()
                .to_lwe_size();

            let mut extracted_bits_blocks = LweCiphertextList::new(
                0u64,
                extract_bits_output_lwe_size,
                LweCiphertextCount(total_bits_extracted),
                self.wopbs_key.param.ciphertext_modulus,
            );

            let mut bits_extracted_so_far = 0;
            // Extraction of each bit for each block
            for block in ct_in.blocks().iter().rev() {
                let block_modulus = block.message_modulus.0 * block.carry_modulus.0;
                let delta = (1_u64 << 63) / (block_modulus / 2);
                // casting to usize is fine, ilog2 of u64 is guaranteed to be < 64
                let delta_log = DeltaLog(delta.ilog2() as usize);
                let nb_bit_to_extract =
                    f64::log2((block.message_modulus.0 * block.carry_modulus.0) as f64) as usize;

                let extract_from_bit = bits_extracted_so_far;
                let extract_to_bit = extract_from_bit + nb_bit_to_extract;
                bits_extracted_so_far += nb_bit_to_extract;

                let mut lwe_sub_list =
                    extracted_bits_blocks.get_sub_mut(extract_from_bit..extract_to_bit);

                self.wopbs_key.extract_bits_assign(
                    delta_log,
                    block,
                    ExtractedBitsCount(nb_bit_to_extract),
                    &mut lwe_sub_list,
                );
            }

            let vec_ct_out = self
                .wopbs_key
                .circuit_bootstrapping_vertical_packing(lut.as_ref(), &extracted_bits_blocks);

            let mut ct_vec_out = vec![];
            for (block, block_out) in ct_in.blocks().iter().zip(vec_ct_out) {
                ct_vec_out.push(crate::shortint::Ciphertext::new(
                    block_out,
                    Degree::new(block.message_modulus.0 - 1),
                    NoiseLevel::NOMINAL,
                    block.message_modulus,
                    block.carry_modulus,
                    block.pbs_order,
                ));
            }
            T::from_blocks(ct_vec_out)
        }

        /// WOPBS for native CRT
        /// # Example
        /// ```rust
        /// use tfhe::integer::gen_keys_crt;
        /// use tfhe::integer::wopbs::WopbsKey;
        /// use tfhe::shortint::parameters::parameters_wopbs_message_carry::WOPBS_PARAM_MESSAGE_4_CARRY_4_KS_PBS;
        ///
        /// let basis: Vec<u64> = vec![9, 11];
        /// let msg_space: u64 = basis.iter().copied().product();
        ///
        /// let param = WOPBS_PARAM_MESSAGE_4_CARRY_4_KS_PBS;
        /// //Generate the client key and the server key:
        /// let (cks, sks) = gen_keys_crt(param, basis);
        /// let wopbs_key = WopbsKey::new_wopbs_key_only_for_wopbs(&cks, &sks);
        ///
        /// let clear = 42 % msg_space; // Encrypt the integers
        /// let ct = cks.encrypt_native_crt(clear);
        /// let lut = wopbs_key.generate_lut_native_crt(&ct, |x| x);
        /// let ct_res = wopbs_key.wopbs_native_crt(&ct, &lut);
        /// let res = cks.decrypt_native_crt(&ct_res);
        /// assert_eq!(res, clear);
        /// ```
        pub fn wopbs_native_crt(
            &self,
            ct1: &CrtCiphertext,
            lut: &IntegerWopbsLUT,
        ) -> CrtCiphertext {
            self.circuit_bootstrap_vertical_packing_native_crt(&[ct1.clone()], lut)
        }

        /// # Example
        /// ```rust
        /// use tfhe::integer::gen_keys_radix;
        /// use tfhe::integer::wopbs::*;
        /// use tfhe::shortint::parameters::parameters_wopbs_message_carry::WOPBS_PARAM_MESSAGE_2_CARRY_2_KS_PBS;
        /// use tfhe::shortint::parameters::PARAM_MESSAGE_2_CARRY_2_KS_PBS_GAUSSIAN_2M64;
        ///
        /// let nb_block = 3;
        /// //Generate the client key and the server key:
        /// let (cks, sks) = gen_keys_radix(PARAM_MESSAGE_2_CARRY_2_KS_PBS_GAUSSIAN_2M64, nb_block);
        ///
        /// // Generate wopbs_v0 key
        /// let wopbs_key = WopbsKey::new_wopbs_key(&cks, &sks, &WOPBS_PARAM_MESSAGE_2_CARRY_2_KS_PBS);
        /// let mut moduli = 1_u64;
        /// for _ in 0..nb_block {
        ///     moduli *= cks.parameters().message_modulus().0;
        /// }
        /// let clear1 = 42 % moduli;
        /// let clear2 = 24 % moduli;
        /// let ct1 = cks.encrypt(clear1);
        /// let ct2 = cks.encrypt(clear2);
        ///
        /// let ct1 = wopbs_key.keyswitch_to_wopbs_params(&sks, &ct1);
        /// let ct2 = wopbs_key.keyswitch_to_wopbs_params(&sks, &ct2);
        /// let lut = wopbs_key.generate_lut_bivariate_radix(&ct1, &ct2, |x, y| 2 * x * y);
        /// let ct_res = wopbs_key.bivariate_wopbs_with_degree(&ct1, &ct2, &lut);
        /// let ct_res = wopbs_key.keyswitch_to_pbs_params(&ct_res);
        /// let res: u64 = cks.decrypt(&ct_res);
        ///
        /// assert_eq!(res, (2 * clear1 * clear2) % moduli);
        /// ```
        pub fn bivariate_wopbs_with_degree<T>(&self, ct1: &T, ct2: &T, lut: &IntegerWopbsLUT) -> T
        where
            T: IntegerCiphertext,
        {
            let ct = ciphertext_concatenation(ct1, ct2);
            self.wopbs(&ct, lut)
        }

        /// # Example
        ///
        /// ```rust
        /// use tfhe::integer::gen_keys_radix;
        /// use tfhe::integer::wopbs::*;
        /// use tfhe::shortint::parameters::parameters_wopbs_message_carry::WOPBS_PARAM_MESSAGE_2_CARRY_2_KS_PBS;
        /// use tfhe::shortint::parameters::PARAM_MESSAGE_2_CARRY_2_KS_PBS_GAUSSIAN_2M64;
        ///
        /// let nb_block = 3;
        /// //Generate the client key and the server key:
        /// let (cks, sks) = gen_keys_radix(PARAM_MESSAGE_2_CARRY_2_KS_PBS_GAUSSIAN_2M64, nb_block);
        ///
        /// //Generate wopbs_v0 key    ///
        /// let wopbs_key = WopbsKey::new_wopbs_key(&cks, &sks, &WOPBS_PARAM_MESSAGE_2_CARRY_2_KS_PBS);
        /// let mut moduli = 1_u64;
        /// for _ in 0..nb_block {
        ///     moduli *= cks.parameters().message_modulus().0;
        /// }
        /// let clear = 42 % moduli;
        /// let ct = cks.encrypt(clear);
        /// let ct = wopbs_key.keyswitch_to_wopbs_params(&sks, &ct);
        /// let lut = wopbs_key.generate_lut_radix(&ct, |x| 2 * x);
        /// let ct_res = wopbs_key.wopbs(&ct, &lut);
        /// let ct_res = wopbs_key.keyswitch_to_pbs_params(&ct_res);
        /// let res: u64 = cks.decrypt(&ct_res);
        ///
        /// assert_eq!(res, (2 * clear) % moduli);
        /// ```
        pub fn generate_lut_radix<F, T>(&self, ct: &T, f: F) -> IntegerWopbsLUT
        where
            F: Fn(u64) -> u64,
            T: IntegerCiphertext,
        {
            let mut total_bit = 0;
            let block_nb = ct.blocks().len();
            let mut modulus = 1;

            //This contains the basis of each block depending on the degree
            let mut vec_deg_basis = vec![];

            for (i, deg) in ct.moduli().iter().zip(ct.blocks().iter()) {
                modulus *= i;
                let b = f64::log2((deg.degree.get() + 1) as f64).ceil() as u64;
                vec_deg_basis.push(b);
                total_bit += b;
            }

            let lut_size = if 1 << total_bit < self.wopbs_key.param.polynomial_size.0 as u64 {
                self.wopbs_key.param.polynomial_size.0
            } else {
                1 << total_bit
            };
            let mut lut =
                IntegerWopbsLUT::new(PlaintextCount(lut_size), CiphertextCount(ct.blocks().len()));

            let basis = ct.moduli()[0];
            let delta: u64 = (1 << 63)
                / (self.wopbs_key.param.message_modulus.0 * self.wopbs_key.param.carry_modulus.0);

            for lut_index_val in 0..(1 << total_bit) {
                let encoded_with_deg_val = encode_mix_radix(lut_index_val, &vec_deg_basis, basis);
                let decoded_val = decode_radix(&encoded_with_deg_val, basis);
                let f_val = f(decoded_val % modulus) % modulus;
                let encoded_f_val = encode_radix(f_val, basis, block_nb as u64);
                for (lut_number, radix_encoded_val) in
                    encoded_f_val.iter().enumerate().take(block_nb)
                {
                    lut[lut_number][lut_index_val as usize] = radix_encoded_val * delta;
                }
            }
            lut
        }

        /// # Example
        /// ```rust
        /// use tfhe::integer::gen_keys_radix;
        /// use tfhe::integer::wopbs::WopbsKey;
        /// use tfhe::shortint::parameters::parameters_wopbs_message_carry::WOPBS_PARAM_MESSAGE_2_CARRY_2_KS_PBS;
        /// use tfhe::shortint::parameters::PARAM_MESSAGE_2_CARRY_2_KS_PBS_GAUSSIAN_2M64;
        ///
        /// let nb_block = 3;
        /// //Generate the client key and the server key:
        /// let (cks, sks) = gen_keys_radix(PARAM_MESSAGE_2_CARRY_2_KS_PBS_GAUSSIAN_2M64, nb_block);
        /// //Generate wopbs_v0 key
        /// let wopbs_key = WopbsKey::new_wopbs_key(&cks, &sks, &WOPBS_PARAM_MESSAGE_2_CARRY_2_KS_PBS);
        /// let mut moduli = 1_u64;
        /// for _ in 0..nb_block {
        ///     moduli *= cks.parameters().message_modulus().0;
        /// }
        /// let clear = 15 % moduli;
        /// let ct = cks.encrypt_without_padding(clear);
        /// let ct = wopbs_key.keyswitch_to_wopbs_params(&sks, &ct);
        /// let lut = wopbs_key.generate_lut_radix_without_padding(&ct, |x| 2 * x);
        /// let ct_res = wopbs_key.wopbs_without_padding(&ct, &lut);
        /// let ct_res = wopbs_key.keyswitch_to_pbs_params(&ct_res);
        /// let res: u64 = cks.decrypt_without_padding(&ct_res);
        ///
        /// assert_eq!(res, (clear * 2) % moduli)
        /// ```
        pub fn generate_lut_radix_without_padding<F, T>(&self, ct: &T, f: F) -> IntegerWopbsLUT
        where
            F: Fn(u64) -> u64,
            T: IntegerCiphertext,
        {
            let log_message_modulus =
                f64::log2((self.wopbs_key.param.message_modulus.0) as f64) as u64;
            let log_carry_modulus = f64::log2((self.wopbs_key.param.carry_modulus.0) as f64) as u64;
            let log_basis = log_message_modulus + log_carry_modulus;
            let delta = 64 - log_basis;
            let nb_block = ct.blocks().len();
            let poly_size = self.wopbs_key.param.polynomial_size.0;
            let mut lut_size = 1 << (nb_block * log_basis as usize);
            if lut_size < poly_size {
                lut_size = poly_size;
            }
            let mut lut = IntegerWopbsLUT::new(PlaintextCount(lut_size), CiphertextCount(nb_block));

            for index in 0..lut_size {
                // find the value represented by the index
                let mut value = 0;
                let mut tmp_index = index;
                for i in 0..nb_block as u64 {
                    let tmp = tmp_index % (1 << (log_basis * (i + 1)));
                    tmp_index -= tmp;
                    value += tmp >> (log_carry_modulus * i);
                }

                // fill the LUTs
                for block_index in 0..nb_block {
                    lut[block_index][index] = ((f(value as u64)
                        >> (log_carry_modulus * block_index as u64))
                        % (1 << log_message_modulus))
                        << delta;
                }
            }
            lut
        }

        /// generate lut for native CRT
        /// # Example
        ///
        /// ```rust
        /// use tfhe::integer::gen_keys_crt;
        /// use tfhe::integer::wopbs::WopbsKey;
        /// use tfhe::shortint::parameters::parameters_wopbs_message_carry::WOPBS_PARAM_MESSAGE_4_CARRY_4_KS_PBS;
        ///
        /// let basis: Vec<u64> = vec![9, 11];
        /// let msg_space: u64 = basis.iter().copied().product();
        ///
        /// let param = WOPBS_PARAM_MESSAGE_4_CARRY_4_KS_PBS;
        /// //Generate the client key and the server key:
        /// let (cks, sks) = gen_keys_crt(param, basis);
        /// let wopbs_key = WopbsKey::new_wopbs_key_only_for_wopbs(&cks, &sks);
        ///
        /// let clear = 42 % msg_space; // Encrypt the integers
        /// let ct = cks.encrypt_native_crt(clear);
        /// let lut = wopbs_key.generate_lut_native_crt(&ct, |x| x);
        /// let ct_res = wopbs_key.wopbs_native_crt(&ct, &lut);
        /// let res = cks.decrypt_native_crt(&ct_res);
        /// assert_eq!(res, clear);
        /// ```
        pub fn generate_lut_native_crt<F>(&self, ct: &CrtCiphertext, f: F) -> IntegerWopbsLUT
        where
            F: Fn(u64) -> u64,
        {
            let mut bit = vec![];
            let mut total_bit = 0;
            let mut modulus = 1;
            let basis: Vec<_> = ct.moduli();

            for i in basis.iter() {
                modulus *= i;
                let b = f64::log2(*i as f64).ceil() as u64;
                total_bit += b;
                bit.push(b);
            }
            let lut_size = if 1 << total_bit < self.wopbs_key.param.polynomial_size.0 as u64 {
                self.wopbs_key.param.polynomial_size.0
            } else {
                1 << total_bit
            };
            let mut lut =
                IntegerWopbsLUT::new(PlaintextCount(lut_size), CiphertextCount(basis.len()));

            for value in 0..modulus {
                let mut index_lut = 0;
                let mut tmp = 1;
                for (base, bit) in basis.iter().zip(bit.iter()) {
                    index_lut += (((value % base) << bit) / base) * tmp;
                    tmp <<= bit;
                }
                for (j, b) in basis.iter().enumerate() {
                    lut[j][index_lut as usize] =
                        (((f(value) % b) as u128 * (1 << 64)) / *b as u128) as u64;
                }
            }
            lut
        }

        /// generate LUt for crt
        /// # Example
        /// ```rust
        /// use tfhe::integer::gen_keys_crt;
        /// use tfhe::integer::wopbs::*;
        /// use tfhe::shortint::parameters::parameters_wopbs_message_carry::WOPBS_PARAM_MESSAGE_3_CARRY_3_KS_PBS;
        /// use tfhe::shortint::parameters::PARAM_MESSAGE_3_CARRY_3_KS_PBS_GAUSSIAN_2M64;
        ///
        /// let basis: Vec<u64> = vec![5, 7];
        /// let msg_space: u64 = basis.iter().copied().product();
        ///
        /// //Generate the client key and the server key:
        /// let (cks, sks) = gen_keys_crt(PARAM_MESSAGE_3_CARRY_3_KS_PBS_GAUSSIAN_2M64, basis);
        /// let wopbs_key = WopbsKey::new_wopbs_key(&cks, &sks, &WOPBS_PARAM_MESSAGE_3_CARRY_3_KS_PBS);
        ///
        /// let clear = 42 % msg_space;
        /// let ct = cks.encrypt(clear);
        /// let ct = wopbs_key.keyswitch_to_wopbs_params(&sks, &ct);
        /// let lut = wopbs_key.generate_lut_crt(&ct, |x| x);
        /// let ct_res = wopbs_key.wopbs(&ct, &lut);
        /// let ct_res = wopbs_key.keyswitch_to_pbs_params(&ct_res);
        /// let res = cks.decrypt(&ct_res);
        /// assert_eq!(res, clear);
        /// ```
        pub fn generate_lut_crt<F>(&self, ct: &CrtCiphertext, f: F) -> IntegerWopbsLUT
        where
            F: Fn(u64) -> u64,
        {
            let mut total_bit = 0;
            let mut modulus = 1;
            let basis = ct.moduli();

            for (i, deg) in basis.iter().zip(ct.blocks.iter()) {
                modulus *= i;
                let b = f64::log2((deg.degree.get() + 1) as f64).ceil() as u64;
                total_bit += b;
            }
            let lut_size = if 1 << total_bit < self.wopbs_key.param.polynomial_size.0 as u64 {
                self.wopbs_key.param.polynomial_size.0
            } else {
                1 << total_bit
            };
            let mut lut =
                IntegerWopbsLUT::new(PlaintextCount(lut_size), CiphertextCount(basis.len()));

            let delta: u64 = (1 << 63)
                / (self.wopbs_key.param.message_modulus.0 * self.wopbs_key.param.carry_modulus.0);

            for i in 0..(1 << total_bit) {
                let mut decomp_terms = Vec::new();
                let mut index_copy = i;
                for (b, block) in basis.iter().zip(ct.blocks.iter()) {
                    let block_bit_count = f64::log2((block.degree.get() + 1) as f64).ceil() as u64;
                    let bits_corresponding_to_block = index_copy % (1 << block_bit_count);
                    let decomp_term = bits_corresponding_to_block % b;
                    index_copy >>= block_bit_count;
                    decomp_terms.push(decomp_term);
                }
                let value_corresponding_to_index = i_crt(&basis, &decomp_terms);
                let f_eval = f(value_corresponding_to_index);
                for (j, block) in ct.blocks.iter().enumerate() {
                    lut[j][i as usize] = (f_eval % block.message_modulus.0) * delta;
                }
            }
            lut
        }

        /// # Example
        ///
        /// ```rust
        /// use tfhe::integer::gen_keys_radix;
        /// use tfhe::integer::wopbs::*;
        /// use tfhe::shortint::parameters::parameters_wopbs_message_carry::WOPBS_PARAM_MESSAGE_2_CARRY_2_KS_PBS;
        /// use tfhe::shortint::parameters::PARAM_MESSAGE_2_CARRY_2_KS_PBS_GAUSSIAN_2M64;
        ///
        /// let nb_block = 3;
        /// //Generate the client key and the server key:
        /// let (cks, sks) = gen_keys_radix(PARAM_MESSAGE_2_CARRY_2_KS_PBS_GAUSSIAN_2M64, nb_block);
        ///
        /// //Generate wopbs_v0 key    ///
        /// let wopbs_key = WopbsKey::new_wopbs_key(&cks, &sks, &WOPBS_PARAM_MESSAGE_2_CARRY_2_KS_PBS);
        /// let mut moduli = 1_u64;
        /// for _ in 0..nb_block {
        ///     moduli *= cks.parameters().message_modulus().0;
        /// }
        /// let clear1 = 42 % moduli;
        /// let clear2 = 24 % moduli;
        /// let ct1 = cks.encrypt(clear1);
        /// let ct2 = cks.encrypt(clear2);
        ///
        /// let ct1 = wopbs_key.keyswitch_to_wopbs_params(&sks, &ct1);
        /// let ct2 = wopbs_key.keyswitch_to_wopbs_params(&sks, &ct2);
        /// let lut = wopbs_key.generate_lut_bivariate_radix(&ct1, &ct2, |x, y| 2 * x * y);
        /// let ct_res = wopbs_key.bivariate_wopbs_with_degree(&ct1, &ct2, &lut);
        /// let ct_res = wopbs_key.keyswitch_to_pbs_params(&ct_res);
        /// let res: u64 = cks.decrypt(&ct_res);
        ///
        /// assert_eq!(res, (2 * clear1 * clear2) % moduli);
        /// ```
        pub fn generate_lut_bivariate_radix<F>(
            &self,
            ct1: &RadixCiphertext,
            ct2: &RadixCiphertext,
            f: F,
        ) -> IntegerWopbsLUT
        where
            RadixCiphertext: IntegerCiphertext,
            F: Fn(u64, u64) -> u64,
        {
            let mut nb_bit_to_extract = [0; 2];
            let block_nb = ct1.blocks.len();
            //ct2 & ct1 should have the same basis
            let basis = ct1.moduli();

            //This contains the basis of each block depending on the degree
            let mut vec_deg_basis = vec![vec![]; 2];

            let mut modulus = 1;
            for (ct_num, ct) in [ct1, ct2].iter().enumerate() {
                modulus = 1;
                for deg in ct.blocks.iter() {
                    modulus *= self.wopbs_key.param.message_modulus.0;
                    let b = f64::log2((deg.degree.get() + 1) as f64).ceil() as u64;
                    vec_deg_basis[ct_num].push(b);
                    nb_bit_to_extract[ct_num] += b;
                }
            }

            let total_bit: u64 = nb_bit_to_extract.iter().sum();

            let lut_size = if 1 << total_bit < self.wopbs_key.param.polynomial_size.0 as u64 {
                self.wopbs_key.param.polynomial_size.0
            } else {
                1 << total_bit
            };
            let mut lut =
                IntegerWopbsLUT::new(PlaintextCount(lut_size), CiphertextCount(basis.len()));
            let basis = ct1.moduli()[0];

            let delta: u64 = (1 << 63)
                / (self.wopbs_key.param.message_modulus.0 * self.wopbs_key.param.carry_modulus.0);

            for lut_index_val in 0..(1 << total_bit) {
                let split = [
                    lut_index_val % (1 << nb_bit_to_extract[0]),
                    lut_index_val >> nb_bit_to_extract[0],
                ];
                let mut decoded_val = [0; 2];
                for i in 0..2 {
                    let encoded_with_deg_val = encode_mix_radix(split[i], &vec_deg_basis[i], basis);
                    decoded_val[i] = decode_radix(&encoded_with_deg_val, basis);
                }
                let f_val = f(decoded_val[0] % modulus, decoded_val[1] % modulus) % modulus;
                let encoded_f_val = encode_radix(f_val, basis, block_nb as u64);
                for (lut_number, radix_encoded_val) in
                    encoded_f_val.iter().enumerate().take(block_nb)
                {
                    lut[lut_number][lut_index_val as usize] = radix_encoded_val * delta;
                }
            }
            lut
        }

        /// generate bivariate LUT for 'fake' CRT
        ///
        /// # Example
        ///
        /// ```rust
        /// use tfhe::integer::gen_keys_crt;
        /// use tfhe::integer::wopbs::*;
        /// use tfhe::shortint::parameters::parameters_wopbs_message_carry::WOPBS_PARAM_MESSAGE_3_CARRY_3_KS_PBS;
        /// use tfhe::shortint::parameters::PARAM_MESSAGE_3_CARRY_3_KS_PBS_GAUSSIAN_2M64;
        ///
        /// let basis: Vec<u64> = vec![5, 7];
        /// let msg_space: u64 = basis.iter().copied().product();
        /// //Generate the client key and the server key:
        /// let (cks, sks) = gen_keys_crt(PARAM_MESSAGE_3_CARRY_3_KS_PBS_GAUSSIAN_2M64, basis);
        /// let wopbs_key = WopbsKey::new_wopbs_key(&cks, &sks, &WOPBS_PARAM_MESSAGE_3_CARRY_3_KS_PBS);
        ///
        /// let clear1 = 42 % msg_space; // Encrypt the integers
        /// let clear2 = 24 % msg_space; // Encrypt the integers
        /// let ct1 = cks.encrypt(clear1);
        /// let ct2 = cks.encrypt(clear2);
        ///
        /// let ct1 = wopbs_key.keyswitch_to_wopbs_params(&sks, &ct1);
        /// let ct2 = wopbs_key.keyswitch_to_wopbs_params(&sks, &ct2);
        ///
        /// let lut = wopbs_key.generate_lut_bivariate_crt(&ct1, &ct2, |x, y| x * y * 2);
        /// let ct_res = wopbs_key.bivariate_wopbs_with_degree(&ct1, &ct2, &lut);
        /// let ct_res = wopbs_key.keyswitch_to_pbs_params(&ct_res);
        /// let res = cks.decrypt(&ct_res);
        /// assert_eq!(res, (clear1 * clear2 * 2) % msg_space);
        /// ```
        pub fn generate_lut_bivariate_crt<F>(
            &self,
            ct1: &CrtCiphertext,
            ct2: &CrtCiphertext,
            f: F,
        ) -> IntegerWopbsLUT
        where
            F: Fn(u64, u64) -> u64,
        {
            let mut nb_bit_to_extract = [0; 2];
            let mut modulus = 1;

            //ct2 & ct1 should have the same basis
            let basis = ct1.moduli();

            for (ct_num, ct) in [ct1, ct2].iter().enumerate() {
                for (i, deg) in basis.iter().zip(ct.blocks.iter()) {
                    modulus *= i;
                    let b = f64::log2((deg.degree.get() + 1) as f64).ceil() as u64;
                    nb_bit_to_extract[ct_num] += b;
                }
            }

            let total_bit: u64 = nb_bit_to_extract.iter().sum();

            let lut_size = if 1 << total_bit < self.wopbs_key.param.polynomial_size.0 as u64 {
                self.wopbs_key.param.polynomial_size.0
            } else {
                1 << total_bit
            };
            let mut lut =
                IntegerWopbsLUT::new(PlaintextCount(lut_size), CiphertextCount(basis.len()));

            let delta: u64 = (1 << 63)
                / (self.wopbs_key.param.message_modulus.0 * self.wopbs_key.param.carry_modulus.0);

            for index in 0..(1 << total_bit) {
                let mut split = encode_radix(index, 1 << nb_bit_to_extract[0], 2);
                let mut crt_value = vec![vec![0; ct1.blocks.len()]; 2];
                for (j, base) in basis.iter().enumerate().take(ct1.blocks.len()) {
                    let deg_1 = f64::log2((ct1.blocks[j].degree.get() + 1) as f64).ceil() as u64;
                    let deg_2 = f64::log2((ct2.blocks[j].degree.get() + 1) as f64).ceil() as u64;
                    crt_value[0][j] = (split[0] % (1 << deg_1)) % base;
                    crt_value[1][j] = (split[1] % (1 << deg_2)) % base;
                    split[0] >>= deg_1;
                    split[1] >>= deg_2;
                }
                let value_1 = i_crt(&ct1.moduli(), &crt_value[0]);
                let value_2 = i_crt(&ct2.moduli(), &crt_value[1]);
                for (j, current_mod) in basis.iter().enumerate() {
                    let value = f(value_1, value_2) % current_mod;
                    lut[j][index as usize] = (value % current_mod) * delta;
                }
            }

            lut
        }

        /// generate bivariate LUT for 'true' CRT
        /// # Example
        ///
        /// ```rust
        /// use tfhe::integer::gen_keys_crt;
        /// use tfhe::integer::wopbs::WopbsKey;
        /// use tfhe::shortint::parameters::parameters_wopbs_message_carry::WOPBS_PARAM_MESSAGE_4_CARRY_4_KS_PBS;
        ///
        /// let basis: Vec<u64> = vec![9, 11];
        /// let msg_space: u64 = basis.iter().copied().product();
        ///
        /// let param = WOPBS_PARAM_MESSAGE_4_CARRY_4_KS_PBS;
        /// //Generate the client key and the server key:
        /// let (cks, sks) = gen_keys_crt(param, basis);
        /// let wopbs_key = WopbsKey::new_wopbs_key_only_for_wopbs(&cks, &sks);
        ///
        /// let clear1 = 42 % msg_space;
        /// let clear2 = 24 % msg_space;
        /// let ct1 = cks.encrypt_native_crt(clear1);
        /// let ct2 = cks.encrypt_native_crt(clear2);
        /// let lut = wopbs_key.generate_lut_bivariate_native_crt(&ct1, |x, y| x * y * 2);
        /// let ct_res = wopbs_key.bivariate_wopbs_native_crt(&ct1, &ct2, &lut);
        /// let res = cks.decrypt_native_crt(&ct_res);
        /// assert_eq!(res, (clear1 * clear2 * 2) % msg_space);
        /// ```
        pub fn generate_lut_bivariate_native_crt<F>(
            &self,
            ct_1: &CrtCiphertext,
            f: F,
        ) -> IntegerWopbsLUT
        where
            F: Fn(u64, u64) -> u64,
        {
            let mut bit = vec![];
            let mut total_bit = 0;
            let mut modulus = 1;
            let basis = ct_1.moduli();
            for i in basis.iter() {
                modulus *= i;
                let b = f64::log2(*i as f64).ceil() as u64;
                total_bit += b;
                bit.push(b);
            }
            let lut_size = if 1 << (2 * total_bit) < self.wopbs_key.param.polynomial_size.0 as u64 {
                self.wopbs_key.param.polynomial_size.0
            } else {
                1 << (2 * total_bit)
            };
            let mut lut =
                IntegerWopbsLUT::new(PlaintextCount(lut_size), CiphertextCount(basis.len()));

            for value in 0..1 << (2 * total_bit) {
                let value_1 = value % (1 << total_bit);
                let value_2 = value >> total_bit;
                let mut index_lut_1 = 0;
                let mut index_lut_2 = 0;
                let mut tmp = 1;
                for (base, bit) in basis.iter().zip(bit.iter()) {
                    index_lut_1 += (((value_1 % base) << bit) / base) * tmp;
                    index_lut_2 += (((value_2 % base) << bit) / base) * tmp;
                    tmp <<= bit;
                }
                let index = (index_lut_2 << total_bit) + (index_lut_1);
                for (j, b) in basis.iter().enumerate() {
                    lut[j][index as usize] =
                        (((f(value_1, value_2) % b) as u128 * (1 << 64)) / *b as u128) as u64;
                }
            }
            lut
        }

        /// bivariate WOPBS for native CRT
        /// # Example
        ///
        /// ```rust
        /// use tfhe::integer::gen_keys_crt;
        /// use tfhe::integer::wopbs::WopbsKey;
        /// use tfhe::shortint::parameters::parameters_wopbs_message_carry::WOPBS_PARAM_MESSAGE_4_CARRY_4_KS_PBS;
        ///
        /// let basis: Vec<u64> = vec![9, 11];
        /// let msg_space: u64 = basis.iter().copied().product();
        ///
        /// let param = WOPBS_PARAM_MESSAGE_4_CARRY_4_KS_PBS;
        /// //Generate the client key and the server key:
        /// let (cks, sks) = gen_keys_crt(param, basis);
        /// let wopbs_key = WopbsKey::new_wopbs_key_only_for_wopbs(&cks, &sks);
        ///
        /// let clear1 = 42 % msg_space;
        /// let clear2 = 24 % msg_space;
        /// let ct1 = cks.encrypt_native_crt(clear1);
        /// let ct2 = cks.encrypt_native_crt(clear2);
        /// let lut = wopbs_key.generate_lut_bivariate_native_crt(&ct1, |x, y| x * y * 2);
        /// let ct_res = wopbs_key.bivariate_wopbs_native_crt(&ct1, &ct2, &lut);
        /// let res = cks.decrypt_native_crt(&ct_res);
        /// assert_eq!(res, (clear1 * clear2 * 2) % msg_space);
        /// ```
        pub fn bivariate_wopbs_native_crt(
            &self,
            ct1: &CrtCiphertext,
            ct2: &CrtCiphertext,
            lut: &IntegerWopbsLUT,
        ) -> CrtCiphertext {
            self.circuit_bootstrap_vertical_packing_native_crt(&[ct1.clone(), ct2.clone()], lut)
        }

        fn circuit_bootstrap_vertical_packing_native_crt<T>(
            &self,
            vec_ct_in: &[T],
            lut: &IntegerWopbsLUT,
        ) -> T
        where
            T: IntegerCiphertext,
        {
            let total_bits_extracted = vec_ct_in.iter().fold(0usize, |acc, ct_in| {
                acc + ct_in.blocks().iter().fold(0usize, |inner_acc, block| {
                    inner_acc
                        + f64::log2((block.message_modulus.0 * block.carry_modulus.0) as f64).ceil()
                            as usize
                })
            });

            let extract_bits_output_lwe_size = self
                .wopbs_key
                .wopbs_server_key
                .key_switching_key
                .output_key_lwe_dimension()
                .to_lwe_size();

            let mut extracted_bits_blocks = LweCiphertextList::new(
                0u64,
                extract_bits_output_lwe_size,
                LweCiphertextCount(total_bits_extracted),
                self.wopbs_key.param.ciphertext_modulus,
            );

            let mut bits_extracted_so_far = 0;
            for ct_in in vec_ct_in.iter().rev() {
                let mut ct_in = ct_in.clone();
                // Extraction of each bit for each block
                for block in ct_in.blocks_mut().iter_mut().rev() {
                    let nb_bit_to_extract =
                        f64::log2((block.message_modulus.0 * block.carry_modulus.0) as f64).ceil()
                            as usize;
                    let delta_log = DeltaLog(64 - nb_bit_to_extract);

                    // trick ( ct - delta/2 + delta/2^4  )
                    lwe_ciphertext_plaintext_sub_assign(
                        &mut block.ct,
                        Plaintext(
                            (1 << (64 - nb_bit_to_extract - 1))
                                - (1 << (64 - nb_bit_to_extract - 5)),
                        ),
                    );

                    let extract_from_bit = bits_extracted_so_far;
                    let extract_to_bit = extract_from_bit + nb_bit_to_extract;
                    bits_extracted_so_far += nb_bit_to_extract;

                    let mut lwe_sub_list =
                        extracted_bits_blocks.get_sub_mut(extract_from_bit..extract_to_bit);

                    self.wopbs_key.extract_bits_assign(
                        delta_log,
                        block,
                        ExtractedBitsCount(nb_bit_to_extract),
                        &mut lwe_sub_list,
                    );
                }
            }

            let vec_ct_out = self
                .wopbs_key
                .circuit_bootstrapping_vertical_packing(lut.as_ref(), &extracted_bits_blocks);

            let mut ct_vec_out = Vec::with_capacity(vec_ct_in.len());
            for (block, block_out) in vec_ct_in[0].blocks().iter().zip(vec_ct_out) {
                ct_vec_out.push(crate::shortint::Ciphertext::new(
                    block_out,
                    Degree::new(block.message_modulus.0 - 1),
                    NoiseLevel::NOMINAL,
                    block.message_modulus,
                    block.carry_modulus,
                    block.pbs_order,
                ));
            }
            T::from_blocks(ct_vec_out)
        }

        pub fn keyswitch_to_wopbs_params<'a, T>(&self, sks: &ServerKey, ct_in: &'a T) -> T
        where
            T: IntegerCiphertext,
            &'a [crate::shortint::Ciphertext]:
                IntoParallelIterator<Item = &'a crate::shortint::Ciphertext>,
        {
            let blocks: Vec<_> = ct_in
                .blocks()
                .par_iter()
                .map(|block| self.wopbs_key.keyswitch_to_wopbs_params(&sks.key, block))
                .collect();
            T::from_blocks(blocks)
        }

        pub fn keyswitch_to_pbs_params<'a, T>(&self, ct_in: &'a T) -> T
        where
            T: IntegerCiphertext,
            &'a [crate::shortint::Ciphertext]:
                IntoParallelIterator<Item = &'a crate::shortint::Ciphertext>,
        {
            let blocks: Vec<_> = ct_in
                .blocks()
                .par_iter()
                .map(|block| self.wopbs_key.keyswitch_to_pbs_params(block))
                .collect();
            T::from_blocks(blocks)
        }
    }
}
